All three game are essentially the same...
Or at least, share most of the same ideas, as did GW's short lived Aeronautica Imperialis
Really its down to which period or genre suits or what your gaming group plays....
However, given the similarities of the rules sets and stats, you can play Luke Skywalker Vs the Red Barron if you want a REALLY silly/fun game....

Having played all of them, there really isn't anything between them in terms of game play, and getting used to pre-painted everything doesnt take that long....